Pterocystis latimarginalis
From Siemensma, 1991

Pterocystis latimarginalis (Dürrschmidt, 1987) Siemensma, 1991

Diagnosis: Periplast 25 µm in diameter, with two types of scales; details of protoplast unknown. Spine scales spoon-shaped, consisting of shaft, lateral wings and basal wing. Shaft, 3-4 µm long and 0.1 µm thick, cylindrical, non-tapering, apically crenulated or abruptly cut off. Proximally, the shaft carries 2 smooth lateral wings in an almost V-form arrangement relative to the main axes and a basal wing, which spreads between the ventral edges of the lateral wings. The proximal shaft end is slightly curved outwards. Plate scales are elliptical or ovoid, 2-2.5 x 1.3-1.6 µm, bordered by a broad radially striated rim, which reaches its max. thickness near the inner edge of this rim. The distinctly denser appearance in TEM shows that this structure is hollow. The central area is smooth, except for a dark central line (axial thickening?).

Distribution: Sri Lanka, Malaysia.

Recent posts

Centropyxiella arenaria

  Centropyxiella arenaria , after Valkanov, 1970   Centropyxiella arenaria  Valkanov, 1970 Diagnosis: Test with almost parallel sides, covered with mineral grains; length varying strongly,

Read More »

Centropyxiella

  Genus Centropyxiella  Valkanov, 1970 Diagnosis: Test with plagiostome, embedded with xenosomes. Border of the pseudostome bent outwardly, in contrary to Centropyxis where the border

Read More »

Centropyxis armata

  Centropyxis armata, after Van Oye, 1952   Centropyxis armata  (Van Oye, 1952) n. comb.Basionym: Cyclopyxis armata Van Oye, 1952 Diagnosis: Test chitinoid, with relatively long

Read More »

Archerella elliptica

  Archerella elliptica, after Van Oye, 1956   Archerella elliptica  (Decloitre, 1974) n. comb.Basionym: Ditrema elliptica Decloitre, 1974   Diagnosis: Test elliptical with two apertures. Dimensions:

Read More »

Archerella jollyi

  Archerella jollyi, after Van Oye, 1956   Archerella jollyi  (Van Oye, 1956) n. comb.Basionym: Amphitrema jollyi Van Oye, 1956   Diagnosis: This species differs

Read More »